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Frustration is a feeling that Internet users also experience when trying to access a website and cannot.
This bad experience is obviously negative for both the user and the website. However, this type of failure can be due to many causes, and these must be studied and, above all, fixed.
In this post, we are going to focus on the error 400 also know as “bad request“, we are going to find out what this error is, its causes and, above all, we are going to explain how to solve it so that it does not negatively affect our website.
What is error 400
To find out what is error 400 we have to know a little better how a website works.
To do this, we need to talk about the status codes in HTTP or in HTTPS (the most used and recommended by Google) and the most common.
HTTP is the acronym for Hypertext Transfer Protocol, that is, hypertext transfer protocol. The HTTPS is the same adding the word safe at the end, that is, through encryption, the data is protected.
This protocol is what allows the web to be displayed to the user. And I’ll explain: when you or any user tries to access a website or web page, it requests information from the server, and it returns a status code.
The codes can be of different types, the ideal is that the code that returns us is 200, that is, a correct request, so the web will be displayed and will work correctly.
However, in this post we are interested in the 400 error or “Bad Request 400” error. This error is due to the previous request that users send before it arrives or is processed by the server.
That is, a “Bad Request” is an error that the server displays when it is unable to include it in any other status category.
So in summary, in general the 400 error will depend on the request sent by the user. But now that we know what this error is, let’s take a look at its main causes.
Causes of the 400 error
Now we are going to tell you the main causes or the most common reasons why we will get a 400 error when we browse the internet:
misspelled url
This is one of the most common causes and it is due to incorrectly writing the URL of the website that we want to visit.
Among the most common errors that we can find in a wrong or misspelled url there are spaces or illegal characters, which will make the server unable to process the request and return a “Bad Request 400”. For example: https:///wordpress/%hosting-wordpress.html
In this example how we see, in the url the character has been entered incorrectly %so the server is unable to show us the url as it is misspelled and we encounter the 400 error.
The correct url would therefore be: https:///wordpress/hosting-wordpress.html
Corrupted files in the cache
There are times that the url that we enter is correct, but nevertheless, we cannot access it and we find the dreaded 400 error.
This is due to there are damaged files in the cache of our browser or that there are problems with cookies. That is, the browser cookies may be expired.
A common example of this case that you have probably experienced is when you try to access your WordPress admin panel after a long period of time. It may be that the start authentication cookies have expired and therefore do not allow you to access, thus showing the 400 or “Bad Request” error.
Bad DNS records
When we browse the internet, the domains we enter are translated into addresses . This process is done when we enter a domain for the first time, which is known as “name resolution”.
Once the server returns an IP address, it is stored locally on our computer (in the local DNS cache), thus allowing the website to load faster.
However, it may happen that the data in the local cache is not correct, wrongly stored, out of sync, or faulty. If this happens, then again we will have the 400 error.
Files too big
In this case, the “Bad Request 400” error will depend more on the server than on the user, as in the rest of the causes that we have mentioned throughout the post. But this cause you must also know.
Uploading files that are too large is another common cause that can lead to the “Bad Request” error.
The server will not be able to process or assume so much information at once, so it will show this error. Although in these cases, it will depend on the server and how it is configured.
Other server errors
The 400 error that we are talking about throughout the article can also be caused by a server problem. This error may be caused by a server failure or due to temporary problems.
In these cases, the error is triggered as a result of the server and not the user, so its control will not be in our hands.
How to fix error 400
Now that we have already talked about the main causes of the 400 error or the “Bad Request” error. It’s time to learn How to solve it when it appears to you
check the url
We have already told you that an incorrect URL is one of the main causes of the 400 error. Therefore, we recommend that you check it if you have entered the URL manually in the browser.
Also, check if the domain is spelled correctly, as well as the specific page you want to access, with all the characters spelled correctly and with the use of slashes (/). Once we have reviewed the url, we can proceed to reload it.
If after checking the syntax of the url it is still not displayed and the “Bad Request 400” error persists, then it is time to clear browser cache and cookies.
Although the cache and cookies are not the same, they are stored in our browser and it is possible that a problem with them is the cause of the error. So as a solution you can try to delete both.
The process to clear the cache and cookies will depend on the browser you normally use to browse the internet. But, in general, you can find this section in the configuration tab of your browser.
Clear the DNS cache
Cleaning the DNS cache is a somewhat more complex process than the previous process and it will depend fundamentally on the operating system you use on your Mac or Windows computer. (You can learn more about it here)
To clear the cache in Windows you will need to go to the “command prompt” application. (You can access it by typing “cmd” in the start search bar). Once open, you must write the command: ‘ipconfig /flushdns’.
If we work with Mac, then you must click on “go” and on the “utilities” bar or on the contrary press shift-command-u. Open the terminal and enter the corresponding clear cache command according to your version.
In both cases you must be the administrator to execute this action.
Upload smaller files
If the error is being caused by the large file uploadtry uploading smaller files.
If the error still persists, then you must find a way to compress these files so that they are uploaded by the server without a problem.
Other solutions
Another solution that we can try if the previous ones have not worked is erase either to disable temporarily some of the browser extensions.
These and/or their cookies may be to blame for the error, so you have nothing to lose by trying.
In summary
As you have been able to learn, this error is much more common than we might expect a priori.
Moreover, this error includes and encompasses a large number of scenarios that we hope that thanks to this article from now on you will know how to identify and face them.
Don’t let a simple 400 error ruin your web browsing experience!
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